Nokia 447ZiPlus - Troubleshooting Guide; Power Start Issues

27
8. TROUBLESHOOTING FLOW CHART
(1) Power Start NG
Power start NG
Is the
voltage at
C815 normal
(125-340V)
?
Does
R808
open?
Is the
start-up
voltage at
C831(16V)
?
Is the
voltage of
R867 normal
(>1Vpp)?
Is
F801
open ?
Check power socket copper and
plug & D811…D814, R805
Check Q868,I862,D831,R867
Check R849, R848, D870, C831,
D831, R831,Q850
Q820,Q821,Q822,
Q823 and their input
control lo
g
ic
Check secondary side circuit.
D802~D807 or any short circuit
on B+ output,R867 resistance
Yes
Yes
Yes
Yes
Yes
N
o
N
o
N
o
N
o
N
o
Replace
F801